Method and means for the execution of coil springs, filaments for incandescent bulbs and the like helically wound parts



J. NAGEL 2,718,914 METHOD AND MEANS FOR THE EXECUTION OF COIL SPRINGS, FILAMENTS FOR INCANDESCENT BULBS AND THE LIKE HELICALLY WOUND PARTS Sept. 27, 1955 4 Sheets-Sheet 1 Filed July 15, 1952 //VI f /l 7 0/9 877 5/ ga Mufa TTORNEYS Sept. 27, 1955 J. NAGEL 2,718,914

METHOD AND MEANS FOR THE EXECUTION OF COIL SPRINGS, FILAMENTS FOR INCANDESCENT BULBS AND THE LIKE HELICALLY WOUND PARTS Filed July 15, 1952 4 Sheets-Sheet 2 //l/I/ 5/V7'0/1: Jean A dge/ Sept. 27, 1955 J. NAGEL 2,718,914

ANS FOR METHOD AND ME THE EXECUTION OF COIL SPRINGS, FIL ENTS FOR INCANDESCENT BULBS AND THE L HELICALLY WOUND PARTS 4 Sheets-Sheet 3 Filed July 15, 1952 A T TORNEYS Sept. 27, 1955 METH D ND MEAN ac gwm INVENTOR J EAN NAGEL ATTORNEYS United States Patent METHOD AND MEANS FDR THE EXECUTION OF COIL SPRINGS, FILAMENTS FOR INCANDES- CENT RULES AND THE LIKE HELICALLY WOUND PARTS Jean Nagel, Paris, France Application July 15, 1952, Serial No. 298,937

Claims priority, application France July 30, 1951 5 Claims. (Cl. 15364) My invention has for its object an improved method and. means for the execution on a commercial scale and at a low cost price of coil springs, filaments for incandescent bulbs and the like helically wound parts, starting from wires or the like material assuming a round, square or the like desired cross section that may be twisted or otherwise, whether said wires are pretreated or not, whether they are soft and but little elastic or else very hard. The wire to be coiled may be bent or crimped before coiling into any regularly recurring succession of saw tooth, square, sinusoidal or like waves so long as it retains at least one longitudinal plane of symmetry, that is to say, so long as the center line of the wire, before coiling, but after bending into wave form, lies in a single plane. It is possible to execute in conformity with my invention helically wound parts the general shape of which is circular, elliptical, square or the like as desired, the pitch and perimetric size of the helical member being unvarying or otherwise.

At the present day, coil springs, filaments for inexerted on it. It is not possible, in accordance with the methods prevailing at the present moment, to execute reliably a helically wound part starting from a wire previously submitted to deformation by bending for instance and made of a soft material of low elasticity as, by reason of the deformations produced, said wire would be submitted to a modification in its main physical properties. It is also impossible to obtain through the method referred to a helically wound part of a very small diameter.

Hitherto it was not possible furthermore to obtain a very fine helically wound part or very long helically wound parts of soft material because the wire could not be wound round the spindle beyond the actual length of the latter, which limited the length of the helically wound part that it was possible to obtain, starting from such a wire. This was for instance the case of the filaments intended for incandescent illuminating bulbs.

My invention has for its object a method and means cutting out the above mentioned drawbacks while allowing a rapid production, without any modification in the physical properties of the wire material, of a helically wound part including a succession of convolutions, whether circular, elliptical, square or the like, the pitch and the perimetric size of which may be constant or variable, starting from wires or the like suitable materials without axially stretching or compressing such wires.

According to my invention, 1 wind the wire to be coiled round a spindle through cooperation of the latter with a dished member provided with a recess assuming the shape of a double cone and engaging the spindle, the geometrical axis of said recess forming an angle with the spindle axis while one of the generating lines of said recess is parallel with the axis of said spindle which rotates at the same angular speed as said dished memice ber. The wire to be coiled is fed tangentially to the spindle so that it may be driven round the latter through cooperation between the adjacent surfaces of the spindle and of the dished member.

The relative movement between the spindle and the dished member will constrain the wire to assume a helical shape, the revolving dished member carrying along with it uninterruptedly and in association with the spindle the wire over said spindle; consequently the wire is not elongated due to a tractional or compressional action exerted thereon.

In a preferred embodiment, there is provided a wire guiding member feeding the wire tangentially to the spindle and there is arranged further between the dished member and a driving head controlling the rotation of the spindle and of the dished member, a pitch-forming member having a helical slope surrounding almost completely the spindle; said slope is located so as to be engaged by the wire to be coiled and to suitably direct it towards the rotary spindle.

The outer shape and the perimeter of the helically wound part are adjusted through the shape and perimeter of the spindle and of the recess in the dished member revolving therewith. A more accurate adjustment of the perimeter may be obtained by modifying the position of the wire guiding member in order to modify the distance between the spindle and the wire fed tangentially to the latter.

The pitch is defined by the pitch adjusting member referred to hereinabove and the helical slope of which surrounds almost completely the spindle. Said helical slope includes in register with the Wire fed by the Wire guiding member a guiding front edge the action of which varies with the angular position given to the pitch adjusting member.

In appended diagrammatic drawings, illustrating said embodiment:

Fig. 1 is an elevational view partly in section, of a machine for coiling a wire in accordance with my invention;

Fig. 2 is a cross section through line IIII of Fig. 1;

Fig. 3 is a detail view of the actual coiling means;

Fig. 4 is a perspective view of the pitch adjusting member;

Figure 5 is an enlarged diagrammatic side view showing the position of the wire relative to the spindle 2 and dished member 6 as it coils about the spindle;

Figure 6 is a diagrammatic cross-section along the line VI-Vl of Figure 5; and

Figure 7 is a view similar to Figure 3 showing a crimped wire passing through my machine.

The machine that serves for coiling wire in conformity with my invention includes, as illustrated, a driving head 1 which may be actuated by a motor or the like driving means of any description; said head carries a spindle 2 which passes through said head and is rigidly and removably secured thereto in any suitable manner. Said head 1 includes a toothed ring 3 which cooperates with a further toothed ring 4 carried by a dished member 5; said dished member is recessed at 6 to form a passage for the spindle, said recess assuming the shape of a double frustocone, i. e. that of two frustoconical chambers 6a and 6b the small ends of which are connected by a short cylindrical channel 6c. Said double frustocone 6 the geometrical axis of which forms an angle with the axis of the spindle 2, has one of its generating lines parallel with said axis of the spindle 2 and is illustrated together with the latter on a larger scale in Fig. 3.

The wire 27 to be coiled is fed tangentially to the spindle 2 and is guided to this end by a thread-guiding member 7 in which is formed a channel 8 and that is located between the driving head 1 and the dished member 5.

There is also fitted between the head 1 and said dished member 5 a member 9 that serves for adjusting the pitch, said member that is illustrated on a larger scale in Fig. 4, being provided with a helically shaped slope 10 that surrounds almost completely the spindle 2. The thread-guiding member 7 and the pitch-adjusting member 8 that are thus mounted side by side between the rotary parts 1 and 5, are located in the vicinity of the opening 11 formed in the head 1 for the passage therethrough of the end of the spindle 2. These members 7 and 9 may be readily replaced without any modification in the scope of the invention by other members playing similar parts.

The normally stationary wire guiding member 7 is adapted to rock round an axis 12 perpendicular to the plate 20 carrying the machine, said axis coinciding with the axis of a screw securing to said plate the block carrying in its turn the member 7; adjustment of the angular location of the system 157 is provided by a screw 13 transversely bearing against said block 15 rigidly secured to the plate said screw 13 engages thus through its end 17 the block 15 carrying the thread-guiding member 7, while a spring 16 bearing against a further block 16a rigid with the plate 20, urges permanently the block 15 through the other side thereof against the said end 17 of the screw 13.

On the other hand, the member 9 that serves for adjusting the pitch is revolubly carried by the plate 20 with reference to the axis of the spindle 2; to this end a screw 18 passing through a recess 19 assuming the shape of an arcuate opening having for its axis the axis of the spindle 2 and formed in the stationary plate 20 allows locking the member 9 in any desired angular position.

The dished member 5 is housed inside a non-rotary ring 21 inside which it may revolve when it is driven into rotation by the head 1 through cooperation between the toothed rings 3 and 4 or through any other suitable equivalent means. When operative, the axis of the ring 21 and of the dished member 5 forms, as already disclosed an angle with the axis of the head 1 and spindle 2. The value of this angle is adjusted through the following means: two rods are provided at 22 that are perpendicular to the stationary plate 20, said rods carrying each a transverse pivot 23, the ring 21 being carried by said pivots 23. The dished member 5 engages through a few teeth of its toothed ring 4 the cooperating teeth of the toothed ring 3, as illustrated in Fig. 2. Said dished member is urged against said toothed ring 3 formed on the driving head 1 by a spring 24 inserted between an adjustable screw 25 screwed into the plate 20 and a stud or screw 26 fitted in the tiltable ring 21.

The screw 2% is a stop which limits the extent to which the spring 24 can draw the dished member 5 towards the toothed ring 3, and is adjustable to permit a very exact regulation of the inclination of the dished member 5 in order to insure the proper engagement of the gear teeth and exact parallelism between the spindle 2 and the cooperating lines through which the conical surfaces 6a and 6b of the dished member 6 pass when in cooperative relationship with said spindle.

The operation of the machine is as follows: the wire 27 is fed through the channel 8 provided in the wire-guiding member so as to engage tangentially the spindle 2, and it is guided for this purpose by the helical slope 10 on the member 9. As the dished member 5 is submitted to the same rotary movement as the winding head 1 and as the spindle 2 is rigid with said head, the wire 27 engaging the space between the spindle 2 and the dished member 5 is wound over the latter by reason of the rotary movement referred to, that is assumed by both parts synchronously, so that the wire engages in a continuous manner the surface of the spindle 2. The recess in the dished member 5 comprises, as stated, the two frustocones 6a and 617 that are connected by the cylindrical throttled part 6c, this having for its result, on one hand, to provide a smoother and more reliable winding of the wire by reason of the longer line of contact between the outer surface of the wire 27 and the wall of the dished member 5 which is, of course, parallel to the line of contact between the inner surface of the wire and the spindle 2, said contact being provided along the lines 6a and 6b as illustrated in Fig. 3 while, on the other hand, this arrangement serves for urging towards one side 6a of the double frustocone the wire 27 engaging the spindle 2 with a force of a magnitude equal to that of the traction exerted on the wire by the frustocone 6b which accounts for the gradual progression of the convolutions of the wire over the spindle 2.

When a motor or the like suitable driving means causes the head 1 and therewith the spindle 2 to rotate in unison with the dished member 5, the wire 27 is drawn in a continuous manner by the associated action of the spindle 2 and of the surface of the recess 6 in the dished member 5, the wire being admitted tangentially by the channel 8 to the spindle 2 and being guided obliquely by the member 9. The coiled wire 27a is fed outwardly through the frustocone 6b. The coiled wire 27a thus produced has a length equal to that of the wire fed to the machine and it is then cut into sections of a predetermined length. The fed wire 27 may be straight or else include deformed parts, e. g. it may be bent at different points.

It is possible to modify the perimeter of the winding within predetermined limits by acting on the guide member 7 through the screw 13 which causes the distance between the wire 27 passing out of the said member 7 and the spindle 2 to be modified through an angular shifting of the wire-guiding member 7 round the axis 12. It is thus possible to modify the perimeter of the helix formed by the wire, even during operation of the machine, since as shown in Figs. 5 and 6 the wire is not snug against the mandrel throughout its circumference, but instead springs slightly away from it on the side opposite the points at which it engages the dished member. Vhen it is desired to modify to a somewhat more considerable extent this perimeter of the convolutions, the spindle 2 should be changed together with the dished member 5 and be replaced by members of a different size. In order to modify the pitch of the convolutions obtained, it is sufficient to shift the member 9 angularly round the spindle 2, the wire 27 engaging the front edge of the helical slope 16 assuming thus a different angularity. It is, therefore, possible to modify the pitch during operation of the machine and this allows executing a coiled wire the pitch of which varies in a continuous manner.

Obviously, various modifications or improvements may be brought to the embodiment disclosed, or various additional features may be incorporated thereto or various parts may be replaced by equivalent means if they do not modify thereby the general scope of the invention as defined in accompanying claims.

What I claim is:

l. A machine for helically winding wires, comprising in combination a cylindrical spindle, means for making said spindle rotate continuously round its axis, a member provided with a channel opening in front of the spindle, a pitch-defining member provided with a helical slope surrounding at least the major part of the spindle periphery and adapted to guide the wire from the outlet of the channel into tangent relationship with reference to an oblique cross-section of the spindle, a recessed member provided with a recess the axis of which forms an acute angle with the axis of the spindle, said recess including two coaxial frustocones surrounding said spindle and connected through their smaller bases and the generating line of each of which lying in the plane of the two axes is parallel with the spindle axis and spaced slightly with reference to the spindle surface, and means constraining said recessed member to rotate round the axis of its recess to cooperate with the rotary spindle for urging the wire forwardly over the spindle.

2. An apparatus for coiling a wire member having at least one longitudinal plane of symmetry, comprising in combination an inner rotatable member having a continuously convex cylindrical external bearing surface, an outer rotatable member having a continuously concave conical internal bearing surface, means for constantly maintaining said bearing surfaces in spaced oppositely facing relation for defining parallel lines of contact separated by a distance corresponding to the thickness of the wire, means for angularly guiding said wire member into the space between said parallel lines of contact and in contacting relation with said bearing surfaces for frictional engagement therebetween at the said lines of contact, and means for rotating said rotatable members in unison.

3. Apparatus as claimed in claim 2 comprising also a driving head rigid with said inner rotatable member and means whereby rotation of said driving turns the outer rotatable member.

4. Apparatus as claimed in claim 2 in which said means for guiding said wire comprises an adjustable channel member opening at a point adjacent said longitudinal member and a pitch-defining member having a helical slope surrounding more than 180 of the inner rotatable member and adapted to guide the wire from the outlet of the channel into said tangent position.

5. The method of helically coiling a wire about an elongated mandrel, said wire having at least one longitudinal plane of symmetry, which comprises the steps of guiding said wire to said mandrel along a path oblique to the longitudinal axis of said mandrel and continuously and uniformly bending said wire about said mandrel by frictionally gripping said wire at a plurality of points forming diametrically opposed parallel lines of contact between said mandrel and a rotatable member, and rotating said rotatable member so that its wire contacting surfaces travel in a frustoconical path about said mandrel.

References Cited in the file of this patent UNITED STATES PATENTS 171,089 Bower Dec. 14, 1875 851,152 Baldwin Apr. 23, 1907 861,608 Richardson July 30, 1907 1,617,445 Gleason Feb. 15, 1927 1,801,102 Mulder Apr. 14, 1931 1,939,581 Tesmer Dec. 12, 1933 2,094,204 Carter Sept. 28, 1937 2,349,828 Moray May 30, 1944 2,453,724 Payne Nov. 16, 1948 FOREIGN PATENTS 639,965 France Mar. 19, 1928 

